Electroluminescent diode array substrate, manufacturing method thereof and display panel

ABSTRACT

An electroluminescent diode array substrate, a method of manufacturing the electroluminescent diode array substrate and a display panel are provided, and the electroluminescent diode array substrate includes: a base substrate; and an auxiliary electrode, a pixel definition layer, a first electrode, a functional layer and a second electrode disposed on the base substrate, the pixel definition layer is provided with a via hole structure, the auxiliary electrode is disposed on at least one side of the via hole structure, and the second electrode is electrically connected with the auxiliary electrode.

The present application claims the priority of the Chinese PatentApplication No. 201710558592.2, filed on Jun. 30, 2017, which isincorporated herein by reference as part of the disclosure of thepresent application.

TECHNICAL FIELD

Embodiments of the present disclosure relate to an electroluminescentdiode array substrate, a method of manufacturing the electroluminescentdiode array substrate, and a display panel.

BACKGROUND

Electroluminescent diodes have advantages of simple manufacturingprocess, low production cost, high light-emitting efficiency, being easyto form flexible structures, low power consumption, high colorsaturation, wide viewing angle, and so on. A display technology by usingelectroluminescent diodes has become an important display technology.

An electroluminescent diode comprises an organic light-emitting diode(OLED), a quantum dot light-emitting diode (QLED) or the like. Forexample, an organic light-emitting diode (OLED) array substratecomprises a plurality of pixel units, and each of the pixel unitscomprises a switching transistor, a driving transistor, an OLED displaydevice and so on. The OLED display device is a current-drivenlight-emitting device, and the OLED display device mainly comprises ananode, a cathode and an organic material functional layer. The workingprinciple of the OLED display device is that the organic materialfunctional layer is driven by an electric field formed by the anode andthe cathode, then carriers are injected and recombined to emit light.The quantum dot light-emitting diode (QLED) has a similar structure tothe organic light-emitting diode (OLED). The main difference between thequantum dot light-emitting diode (QLED) and the organic light-emittingdiode is that the luminescence center of the QLED is composed of quantumdots, and the light-emitting principle of the quantum dot light-emittingdiode (QLED) is that electrons and holes are combined to form photons ina quantum dot layer, then the photons are recombined to emit light.

SUMMARY

At least one embodiment of the present disclosure provides anelectroluminescent diode array substrate, and the electroluminescentdiode array substrate includes: a base substrate, and an auxiliaryelectrode, a pixel definition layer, a first electrode, a functionallayer, and a second electrode which are disposed on the base substrate,and the pixel definition layer is provided with a via hole structure;the auxiliary electrode is disposed on at least one side of the via holestructure; and the second electrode is electrically connected with theauxiliary electrode.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, an upper surface ofthe auxiliary electrode is higher than an upper surface of thefunctional layer in the via hole structure.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, the auxiliaryelectrode is a structure in a U shape.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, the auxiliaryelectrode is a plate-type structure; or there are a plurality ofauxiliary electrodes which are spaced apart from each other.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, a conductive polymerlayer is provided in the via hole structure, and the second electrode iselectrically connected with the auxiliary electrode by the conductivepolymer layer.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, a thickness of theconductive polymer layer is less than a thickness of the pixeldefinition layer.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, a conductivity of theconductive polymer layer is greater than 10⁻⁶ S/m.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, a material of theconductive polymer layer comprises at least one of polypyrrole,polyphenylene sulfide, polyphthalocyanine, polyaniline andpolythiophene.

For example, the electroluminescent diode array substrate provided by atleast one embodiment of the present disclosure, further includes aplanarization layer disposed between the base substrate and the pixeldefinition layer, and the via hole structure extends from the pixeldefinition layer and penetrates through the planarization layer.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, a thickness of theconductive polymer layer is larger than a thickness of the planarizationlayer, and the thickness of the conductive polymer layer is smaller thana sum of the thickness of the planarization layer and a thickness of thepixel definition layer.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, an upper surface ofthe conductive polymer layer is flush with an upper surface of the pixeldefinition layer.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, there are a pluralityof via hole structures penetrating through the planarization layer andthe pixel definition layer, and the second electrode is electricallyconnected with the auxiliary electrode by the plurality of via holestructures.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, a thickness of thefunctional layer is from about 100 nm to about 300 nm, a thickness ofthe auxiliary electrode is from about 0.5 μm to about 1 μm, a thicknessof the planarization layer is from about 1 μm to about 3 μm, a thicknessof the pixel definition layer is from about 1 μm to about 3 μm, and athickness of the conductive polymer layer is from about 2 μm to about5.7 μm.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the present disclosure, the functional layercomprises at least one of a light-emitting layer, an electron injectionlayer, an electron transmission layer, a hole injection layer and a holetransmission layer.

At least one embodiment of the present disclosure further provides adisplay panel, and the display panel includes any one of theelectroluminescent diode array substrate described above.

At least one embodiment of the present disclosure further provides amethod of manufacturing an electroluminescent diode array substrate, andthe method includes: providing a base substrate, forming an auxiliaryelectrode, a pixel definition layer, a first electrode, a functionallayer and a second electrode on the base substrate, and the pixeldefinition layer is provided with a via hole structure; the auxiliaryelectrode is disposed on at least one side of the via hole structure;and the second electrode is electrically connected with the auxiliaryelectrode.

For example, in the method provided by at least one embodiment of thepresent disclosure, an upper surface of the auxiliary electrode which isformed on at least one side of the via hole structure is higher than anupper surface of the functional layer in the via hole structure.

For example, the method provided by at least one embodiment of thepresent disclosure, before forming the auxiliary electrode, furtherincludes: forming a planarization layer on the base substrate, whereinthe via hole structure extends from the pixel definition layer andpenetrates through the planarization layer.

For example, the method provided by at least one embodiment of thepresent disclosure, further includes: forming a conductive polymer layerin the via hole structure, wherein the second electrode is electricallyconnected with the auxiliary electrode by the conductive polymer layer.

For example, in the method provided by at least one embodiment of thepresent disclosure, the conductive polymer layer is formed by an inkjetprinting method.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to clearly illustrate the technical solution of the embodimentsof the disclosure, the drawings of the embodiments will be brieflydescribed. It is apparent that the described drawings are only relatedto some embodiments of the disclosure and thus are not limitative of thedisclosure.

FIG. 1 is a schematic sectional view of an organic light-emitting diode(OLED) array substrate;

FIG. 2 is a schematic sectional view of an OLED array substrate providedby an embodiment of the present disclosure;

FIG. 3 is a schematic view of a planar structure of an OLED arraysubstrate provided by an embodiment of the present disclosure;

FIG. 4 is a schematic sectional view of an OLED array substrate providedby another embodiment of the present disclosure;

FIG. 5 is a schematic sectional view of an OLED array substrate providedby still another embodiment of the present disclosure;

FIG. 6 is a schematic sectional view of an OLED array substrate providedby still another embodiment of the present disclosure;

FIG. 7 is a schematic sectional view of an OLED array substrate providedby still another embodiment of the present disclosure;

FIG. 8 is a block diagram of a display panel provided by an embodimentof the present disclosure; and

FIG. 9 is a flow diagram of a manufacturing method of an OLED arraysubstrate provided by an embodiment of the present disclosure.

REFERENCE NUMERALS

101, 201—base substrate; 102, 202—auxiliary electrode; 103,203—planarization layer; 104, 204—first electrode; 105—organic materialfunctional layer; 205—functional layer; 106, 206—second electrode; 107,207—via hole structure; 108, 208—pixel definition layer; 209—conductivepolymer layer; 1—display panel; 2—electroluminescent diode arraysubstrate; 20—OLED device; 30—switching transistor; 40—drivingtransistor.

DETAILED DESCRIPTION

In order to make objects, technical details and advantages ofembodiments of the disclosure clear, the technical solutions of theembodiments will be described in a clearly and fully understandable wayin connection with the related drawings. It is apparent that thedescribed embodiments are just a part but not all of the embodiments ofthe disclosure. Based on the described embodiments herein, those skilledin the art can obtain, without any inventive work, other embodiment(s)which should be within the scope of the disclosure.

Unless otherwise defined, all the technical and scientific terms usedherein have the same meanings as commonly understood by one of ordinaryskill in the art to which the present invention belongs. The terms“first,” “second,” etc., which are used in the description and claims ofthe present application, are not intended to indicate any sequence,amount or importance, but distinguish various components. The terms“comprises,” “comprising,” “includes,” “including,” etc., are intendedto specify that the elements or the objects stated before these termsencompass the elements or the objects listed after these terms as wellas equivalents thereof, but do not exclude other elements or objects.The phrases “connect”, “connected”, etc., are not intended to define aphysical connection or mechanical connection, but may include anelectrical connection which is direct or indirect. The terms “on,”“under,” “right,” “left” and the like are only used to indicate relativeposition relationship, and when the position of an object is describedas being changed, the relative position relationship may be changedaccordingly.

Electroluminescent diodes, for example, organic light-emitting diodes(OLED) and quantum dot light-emitting diodes (QLED) are mostlycurrent-driven devices. In a case where an external circuit used forproviding a driving current is too long or too thin, the externalcircuit leads to a serious voltage gradient (a voltage drop). To reducethe voltage drop, an auxiliary electrode is usually added in anelectroluminescent diode display device. For example, the auxiliaryelectrode is formed on the electroluminescent diode array substrate, andthe auxiliary electrode is electrically connected with a cathode by avia hole structure. However, in the process of manufacturing an OLEDdevice, especially in the process of manufacturing a large-sized OLEDpanel, an organic material is evaporated at the via hole structure, andthe organic material separates the cathode from the auxiliary electrode.In the process of manufacturing a QLED device, especially in the processof manufacturing a large-sized QLED panel, a quantum dot light-emittinglayer is printed at the via hole structure, and the quantum dotlight-emitting layer separates the cathode from the auxiliary electrode.

For example, the organic light-emitting diode array substrate is takenfor an example. FIG. 1 is a schematic sectional view of an organiclight-emitting diode (OLED) array substrate. As illustrated in FIG. 1,the organic light-emitting diode array substrate comprises: a basesubstrate 101; and an auxiliary electrode 102, a planarization layer103, a first electrode 104, an organic material functional layer 105, asecond electrode 106 and a pixel definition layer 108 disposed on thebase substrate; and the planarization layer 103 is provided with a viahole structure 107.

For example, the second electrode 106 of the OLED array substrate isgenerally made of metallic silver with a thinner thickness, and thefirst electrode 104 is generally made of indium tin oxide (ITO), andboth the resistivity of the metal silver with a thinner thickness andthe resistivity of the indium tin oxide (ITO) are high, and especiallyfor the second electrode 106 with a large area, the second electrode 106made of the thin metal silver has a higher resistivity, and the voltagedrop (IR drop) is larger; in this case, the actual driving voltage ofthe OLED array substrate is greatly different from a power voltage, andin a large-sized OLED display device, a large area of uneven brightnessphenomenon occurs, which affects the display effect. As illustrated inFIG. 1, the auxiliary electrode 102 formed on the base substrate 102reduces the resistance of the second electrode 106. However, thesubsequently formed organic material functional layer 105 separates theauxiliary electrode 102 from the second electrode 106, thus theauxiliary electrode 102 can't be in parallel connect with the secondelectrode 106, and can't reduce the voltage drop effectively.

The inventor of the present disclosure notes that changing thestructural design of the auxiliary electrode can ensure that the secondelectrode is electrically connected with the auxiliary electrode, inthis way, the auxiliary electrode electrically connected with the secondelectrode increases the equivalent thickness of the second electrode,thereby the resistance of the second electrode is reduced, and theproblem that the large voltage drop caused by the large resistance ofthe second electrode in a case where the second electrode made ofmetallic silver with a thinner thickness is avoided, furthermore, theproblem of damaging an organic light-emitting display panel due to thelarge voltage drop is avoided as well.

At least one embodiment of the present disclosure provides anelectroluminescent diode array substrate, and the electroluminescentdiode array substrate comprises: a base substrate, and an auxiliaryelectrode, a pixel definition layer, a first electrode, a functionallayer, and a second electrode, which are disposed on the base substrate;the pixel definition layer is provided with a via hole structure; theauxiliary electrode is disposed on at least one side of the via holestructure; and the second electrode is electrically connected with theauxiliary electrode. The embodiment of the present disclosure ensuresthat the second electrode is electrically connected with the auxiliaryelectrode by changing the structural design of the auxiliary electrode,thereby the problem of the large voltage drop in the external circuit isavoided.

At least one embodiment of the disclosure provides an electroluminescentdiode array substrate, and the electroluminescent diode array substrateis an organic light-emitting diode (OLED) array substrate or a quantumdot light-emitting diode (QLED) array substrate. The following isillustrated by taking the electroluminescent diode array substrate asthe organic light-emitting diode (OLED) array substrate for example.

For example, FIG. 2 is a schematic sectional view of an OLED arraysubstrate provided by at least one embodiment of the present disclosure.As illustrated in FIG. 2, the organic light-emitting diode arraysubstrate 2 comprises: a base substrate 201, and an auxiliary electrode202, a pixel definition layer 208, a first electrode 204, a functionallayer 205 (for example, an organic material functional layer) and asecond electrode 206 disposed on the base substrate 201, the pixeldefinition layer 208 is provided with a via hole structure 207, theauxiliary electrode 202 is disposed on at least one side of the via holestructure 207, and the second electrode 206 is electrically connectedwith the auxiliary electrode 202.

It should be noted that, the auxiliary electrode disposed on at leastone side of the via hole structure not means that the auxiliaryelectrode is disposed on the outside or the inside of the via holestructure, but means that the auxiliary electrode is disposed on a sidewall of at least one direction of the outside side of the via holestructure.

For example, an upper surface of the auxiliary electrode 202 is higherthan an upper surface of the functional layer 205 of the via holestructure 207.

For example, the OLED array substrate includes a display region and aperipheral region outside the display region. The display region is alsoreferred to as an AA (Active Area), and the display region is generallyused for displaying. The peripheral region may be used for arranging adriving circuit, packaging a display panel, and the like. For example,in the peripheral region, the second electrode 206 is electricallyconnected with the auxiliary electrode 202, and in the display region,the second electrode 206 is electrically connected with the auxiliaryelectrode 202, in this way, the second electrode 206 and the auxiliaryelectrode 202 are connected at both ends respectively to form aparallel-connected circuit, or both ends that the second electrode 206and the auxiliary electrode 202 connected to each other are located inthe display region. In a case where the second electrode 206 receives avoltage signal and transmits the voltage signal, and the voltage signalreaches the auxiliary electrode 202 that electrically connected to thesecond electrode 206, the auxiliary electrode 202 transmits the voltagesignal simultaneously with the second electrode 206 as a branch of thevoltage signal, which is equivalent to that the second electrode 206 andthe auxiliary electrode 202 form the parallel-connected circuit, in thisway, the resistance in the process of electrical signal transmission isreduced; or the auxiliary electrode 202 receives the voltage signalfirstly, in a case where the voltage signal reaches the second electrode206 electrically connected to the auxiliary electrode 202, the secondelectrode 206 as a branch for transmitting the voltage signalsimultaneously with the auxiliary electrode 202; or the second electrode206 and the auxiliary electrode 202 receives the voltage signalsimultaneously, the second electrode 206 and the auxiliary electrode 202transmit the voltage signal simultaneously as two branches.

For example, as illustrated in FIG. 3, the OLED array substrate 2further includes a power line, a data line and a gate line (not shown inFIG. 3) disposed on the base substrate 201, a pixel structure isdisposed in a region defined by the gate line and the data lineintersecting with each other, for example, the pixel structure includesa switching transistor 30, a driving transistor 40, and an OLED device20, and the switching transistor 30 is connected to the gate line andthe data line, the driving transistor 40 is connected to the switchingtransistor 30, the power line, and the OLED device.

For example, as illustrated in FIG. 2 and FIG. 3, the pixel definitionlayer 208 is located between the first electrode 204 and the secondelectrode 206, and the pixel definition layer 208 is used for isolatingtwo sub-pixel units adjacent to each other.

For example, the pixel structure, the gate line and the data line arelocated in the display region, in addition to the gate line and the dataline, the OLED array substrate may further include a detectioncompensation line connecting a pixel unit and a detection integratedcircuit. The detection compensation line is located in the displayregion.

For example, as illustrated in FIG. 2, the upper surface of theauxiliary electrode 202 on at least one side of the via hole structure207 is higher than the upper surface of the functional layer 205 in thevia hole structure 207, in this way, the auxiliary electrode 202 iselectrically connected to the second electrode 206 through the portionof the auxiliary electrode that higher than the upper surface of thefunctional layer 205 in the via hole structure 207.

For example, FIG. 4 is a schematic sectional view of an OLED arraysubstrate provided by another embodiment of the present disclosure. Asillustrated in FIG. 4, the organic light-emitting diode array substratefurther includes a planarization layer 203 disposed between the basesubstrate 201 and the pixel definition layer 208, in which the via holestructure 207 extends from the pixel definition layer 208 and penetratesthrough the planarization layer 203.

For example, as illustrated in FIG. 4, the via hole structure 207extends from pixel definition layer 208 and penetrates throughplanarization layer 203. In this way, the depth of the via holestructure 207 is approximately equal to the sum of the thickness of thepixel definition layer 208 and the thickness of the planarization layer203.

For example, in the embodiment of the present disclosure, the thicknessof the functional layer 205 is from about 100 nm to about 300 nm, forexample, the thickness of the functional layer 205 is 100 nm, 200 nm or300 nm, etc.

For example, the thickness of auxiliary electrode 202 is from about 0.5μm to about 1 μm, such as 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm or 1μm, etc.

For example, the thickness of planarization layer 203 is from about 1 μmto about 3 μm, such as 1 μm, 2 μm or 3 μm, etc.

For example, the thickness of the pixel definition layer 208 is fromabout 1 μm to about 3 μm, such as 1 μm, 2 μm or 3 μm, etc.

For example, the thickness of the first electrode 204 is from about 200μm to about 300 μm, for example, 200 μm, 250 μm, or 300 μm, etc.

For example, the thickness of the second electrode 206 is from about 100μm to about 200 μm, for example, 100 μm, 150 μm, or 200 μm, etc.

For example, in a case where the second electrode 206 is directlyconnected to the auxiliary electrode 202, the second electrode 206 mayhave a segment difference (step), that is, the second electrode 206 isbroken. A conductive polymer layer 209 is arranged in the via holestructure 207 to raise the functional layer 205 so as to prevent thesecond electrode 206 from breaking, as illustrated in FIG. 2 and FIG. 4,the conductive polymer layer 209 is formed between the auxiliaryelectrode 202 and the second electrode 206. The second electrode 206 iselectrically connected with the auxiliary electrode 202 through theconductive polymer layer 209 to reduce the risk of forming a segmentdifference of the second electrode 206.

For example, the thickness of the conductive polymer layer 209 is largerthan the thickness of the planarization layer 203, and the thickness ofthe conductive polymer layer 209 is smaller than the sum of thethickness of the planarization layer 203 and the thickness of the pixeldefinition layer 208.

For example, the upper surface of the conductive polymer layer 209 isflush with the upper surface of the pixel definition layer 208, in thisway, the risk that the second electrode 206 having a segment differenceis basically eliminated.

For example, the thickness of the conductive polymer layer 209 is fromabout 2 μm to about 5.7 μm. For example, the thickness of the conductivepolymer layer is 2 μm, 3 μm, 4 μm or 5 μm, etc.

For example, the conductivity of the conductive polymer layer is greaterthan 10⁻⁶ S/m, which ensures that the auxiliary electrode 202 iselectrically connected with the second electrode 206.

For example, a material of the conductive polymer layer 209 comprises atleast one of polypyrrole, polyphenylene sulfide, polyphthalocyanine,polyaniline and polythiophene.

For example, FIG. 5 is a schematic sectional view of an OLED arraysubstrate provided by still another embodiment of the presentdisclosure. As illustrated in FIG. 5, the auxiliary electrode 202 in thevia hole structure 207 is a structure in a U shape, it is equivalent totwo side walls of the auxiliary electrode 202 being raised so that thesecond electrode 206 is directly electrically connected with theauxiliary electrode 202 at the via hole structure 207, thus the step offorming the conductive polymer layer is reduced, and the risk of forminga segment difference of the second electrode 206 reduced.

It should be noted that, the auxiliary electrode 202 is a structure in aU shape means that in the direction perpendicular to the surface of thebase substrate 201, the cross-section structure of the auxiliaryelectrode (for example, the longitudinal cross-section of the auxiliaryelectrode) is in a concave shape.

For example, FIG. 6 is a schematic sectional view of an OLED arraysubstrate provided by still another embodiment of the presentdisclosure. For example, the conductive polymer layer 209 is formed onthe auxiliary electrode 202 in a U shape, which further reduces the riskof forming the segment difference of the second electrode 206.

For example, the auxiliary electrode 202 is a plate-type structure, andthe via hole structure 207 is at least covered with the auxiliaryelectrode 202; or, on a plane parallel to the surface of the basesubstrate 201 and along the extension direction of the via holestructure 207, there are a plurality of auxiliary electrodes 202, andthe plurality of auxiliary electrodes 202 are spaced apart from eachother.

For example, FIG. 7 is a schematic sectional view of an OLED arraysubstrate provided by still another embodiment of the presentdisclosure. As illustrated in FIG. 7, the electroluminescent diode arraysubstrate comprises a plurality of via hole structures 207 penetratingthrough the planarization layer 203 and the pixel definition layer 208,and the second electrode 206 is electrically connected with theauxiliary electrodes 202 by the plurality of via hole structures 207, sothat the second electrode 206 is connected in parallel with theauxiliary electrodes 202 respectively. FIG. 7 shows two via holestructures 207. Obviously, the number of the via hole structures in theembodiments of the present disclosure is not limited to the aboveexample, and more via hole structures 207 can be formed to furtherreduce the resistance of the second electrode and the auxiliaryelectrodes, in addition, the second electrode 206 connected in parallelwith the auxiliary electrodes 202 through the plurality of via holestructures 207 increases the thickness of the second electrode 206,which is equivalent to increasing of the cross-sectional area of thesecond electrode 206, and the resistance of the second electrode 206 isfurther reduced.

For example, the pixel definition layer 208 is made of an organicinsulating material (for example, an acrylic resin) or an inorganicinsulating material (for example, silicon nitride SiNx or silicon oxideSiOx), the pixel definition layer 208 has an insulating property. Thepixel definition layer 208 may be considered as the insulating structuredisposed between the second electrode 206 and the auxiliary electrode202.

For example, the first electrode 205 is made of a transparent conductivematerial, and the transparent conductive material includes indium tinoxide (ITO), indium zinc oxide (IZO), indium gallium oxide (IGO), zincgallium oxide (GZO)), Indium oxide (In₂O₃), aluminum zinc oxide (AZO)and carbon nanotubes.

For example, the first electrode 205 is made of a metal conductivematerial, and the metal conductive material includes a single metal suchas Cu, Cr, Mo, Au, Ag and Pt metal, or an alloy material formed of theabove metals, for example, a copper chromium alloy (CuCr) or a chromiummolybdenum alloy (CrMo).

For example, the first electrode 205 is a stacked structure formed byany combination of the above-mentioned transparent conductive materialand the metal conductive material. For example, the first electrode 205is in a structure that the metal conductive material is sandwichedbetween two transparent conductive materials, such as ITO-Mo-IZO,ITO-Cr—In2O3, ITO-Cu—ZnO and ITO-Pt-IGO, or the first electrode 205 is astacked double-layer structure made of the metal conductive material andthe transparent conductive material, such as IZO—Mo, ITO-Cr, ZnO—Mg andITO-Au. For example, the stacked structure formed of any combination ofthe transparent conductive material and the metal conductive material isnot limited to the stacked double-layer structure and the stackedtriple-layer structure. It may also be a stacked structure with multiplelayers of other layers, for example, a stacked structure of four layers,a stacked structure of five layers, etc.

It should be noted that, because the work function of the metal materialor the work function of the alloy material for forming the firstelectrode is relatively low, the first electrode has poor compatibilitywith the organic material functional layer in the OLED array substrate.The transparent conductive material formed on a side of the first metallayer close to the functional layer formed of the organic materialimproves the work function of the first metal, so that the firstelectrode is better matched with the functional layer formed of theorganic material. In addition, the first electrode of the double-layerstructure or the triple-layer structure has a lower resistance than thefirst electrode of the single-layer structure, and the resistance of thefirst electrode is lower, in this way, the resistance of the firstelectrode is reduced.

For example, the material of the second electrode 206 includesmagnesium, aluminum, lithium or other single metal, or magnesiumaluminum alloy (MgAl), lithium aluminum alloy (LiAl), and the like.

For example, in the electroluminescent diode array substrate provided byat least one embodiment of the disclosure, taking the array substrate asthe organic light-emitting diode (OLED) array substrate as an example,this functional layer includes a light-emitting layer, an electroninjection layer, an electron transmission layer, a hole injection layerand a hole transmission layer.

For example, the method of manufacturing the functional layer in theorganic light-emitting diode (OLED) array substrate includes a vacuumevaporation method and a solution method. The vacuum evaporation methodis suitable for small organic molecules without solvent, and thethicknesses of each layers of organic material functional layer isuniform. The solution method includes a spin coating method, an inkjetprinting method and a nozzle coating method, and the solution method issuitable for polymer materials and soluble small molecules, it has theadvantage of low cost in production equipment, and has outstandingadvantages in the production of large-scale and large-sized products,especially, the inkjet printing technology can accurately spray solutionto the pixel region.

It should be noted that, unlike the organic light-emitting diode (OLED)array substrate, the quantum dots in the self-luminescent quantum dotslight-emitting diodes (QLED) cannot adopt the same evaporation method asthe self-luminescent OLEDs, due to the phenomenon that the quantum dotsare easy to be affected by heat and moisture, and therefore only theink-jet printing can be used.

At least one embodiment of the present disclosure further provides adisplay panel, and the display panel includes any one of theelectroluminescent diode array substrate described above.

For example, FIG. 8 is a block diagram of a display panel provided by anembodiment of the present disclosure. As illustrated in FIG. 8, thedisplay panel 1 includes an electroluminescent diode array substrate 2disposed therein. For example, the display panel 1 can be applied to adisplay apparatus, for example, the display apparatus is a mobile phone,a tablet computer, a television, a display, a notebook computer, adigital picture frame, a navigation system and any other product orcomponent having a display function. The embodiments of the displayapparatus can be referred to the above embodiments of theelectroluminescent diode array substrate, which is omitted herein.

At least one embodiment of the present disclosure further provides amethod of manufacturing an electroluminescent diode array substrate, andthe electroluminescent diode array substrate is an organiclight-emitting diode (OLED) array substrate or a quantum dotlight-emitting diode (QLED) array substrate. The following isillustrated by taking the electroluminescent diode array substrate asthe organic light-emitting diode (OLED) array substrate for example.

For example, FIG. 9 is a flow diagram of a manufacturing method of anOLED array substrate provided by an embodiment of the presentdisclosure. For example, the manufacturing method comprises thefollowing steps:

S101: providing a base substrate.

S102: forming an auxiliary electrode, a pixel definition layer, a firstelectrode, a functional layer and a second electrode on the basesubstrate, in which forming of the pixel definition layer includesforming a via hole structure in the pixel definition layer, theauxiliary electrode is on at least one side of the via hole structure,and the second electrode is electrically connected with the auxiliaryelectrode.

For example, in the manufacturing method provided by at least oneembodiment of the present disclosure, the upper surface of the auxiliaryelectrode on at least one side of the via hole structure is higher thanthe upper surface of the functional layer in the via hole structure, inthis way, the auxiliary electrode is electrically connected to thesecond electrode through the portion of the auxiliary electrode thathigher than the upper surface of the functional layer in the via holestructure.

For example, a planarization layer is formed before forming the pixeldefinition layer, and the via hole structure extends from the pixeldefinition layer to penetrate through the planarization layer, and thepixel definition layer is used for isolating two sub-pixel unitsadjacent to each other.

For example, the second electrode is electrically connected with theauxiliary electrodes by the plurality of via hole structures, so thatthe second electrode is connected in parallel with the auxiliaryelectrodes respectively. In addition, the second electrode connected inparallel with the auxiliary electrodes through the plurality of via holestructures increases the thickness of the second electrode, which isequivalent to increasing of the cross-sectional area of the secondelectrode, and the resistance of the second electrode 206 is furtherreduced.

For example, the pixel definition layer is made of an organic insulatingmaterial (for example, an acrylic resin) or an inorganic insulatingmaterial (for example, silicon nitride SiNx or silicon oxide SiOx), thepixel definition layer has an insulating property. The pixel definitionlayer may be considered as the insulating structure disposed between thesecond electrode and the auxiliary electrode.

For example, the manufacturing method provided by at least oneembodiment of the present disclosure further includes forming aconductive polymer layer in the via hole structure, and the secondelectrode is electrically connected with the auxiliary electrode by theconductive polymer layer. In a case where the second electrode isdirectly connected to the auxiliary electrode, the second electrode mayhave a segment difference, that is, the second electrode is broken. Theconductive polymer layer is arranged in the via hole structure to raisethe functional layer so as to prevent the second electrode frombreaking.

For example, the thickness of the conductive polymer layer is largerthan the thickness of the planarization layer, and the thickness of theconductive polymer layer is smaller than the sum of the thickness of theplanarization layer and the thickness of the pixel definition layer.

For example, the upper surface of the conductive polymer layer is flushwith an upper surface of the pixel definition layer, in this way, therisk that the second electrode having a segment difference is basicallyeliminated.

For example, the thickness of the conductive polymer layer is from about2 μm to about 5.7 μm. For example, the thickness of the conductivepolymer layer is 2 μm, 3 μm, 4 μm or 5 μm, etc.

For example, the conductivity of the conductive polymer layer is greaterthan 10⁻⁶ S/m, which ensures that the auxiliary electrode iselectrically connected with the second electrode.

For example, the material of the conductive polymer layer comprises atleast one of polypyrrole, polyphenylene sulfide, polyphthalocyanine,polyaniline and polythiophene.

For example, in the manufacturing method provided by the embodiment ofthe present disclosure, the conductive polymer layer is formed by aninkjet printing method.

For example, in an embodiment of the present disclosure, the thicknessof the functional layer is from about 100 nm to about 300 nm, forexample, the thickness of the functional layer is 100 nm, 200 nm or 300nm, etc.

For example, the thickness of auxiliary electrode 202 is from about 0.5μm to about 1 μm, such as 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm or 1μm, etc.

For example, the thickness of planarization layer 203 is from about 1 μmto about 3 μm, such as 1 μm, 2 μm or 3 μm, etc.

For example, the thickness of the pixel definition layer 208 is fromabout 1 μm to about 3 μm, such as 1 μm, 2 μm or 3 μm, etc.

For example, thickness of the first electrode 204 is from about 200 μmto about 300 μm, for example, 200 μm, 250 μm, or 300 μm, etc.

For example, the thickness of the second electrode 206 is from about 100μm to about 200 μm, for example, 100 μm, 150 μm, or 200 μm, etc.

The electroluminescent diode array substrate, the method ofmanufacturing the electroluminescent diode array substrate and thedisplay panel provided by the embodiments of the present disclosure haveat least one of the following beneficial effects:

(1) in the electroluminescent diode array substrate provided by at leastone embodiment of the present disclosure, by changing the structuraldesign of the auxiliary electrode, the electrical connection between thesecond electrode and the auxiliary electrode is ensured, in this way,the auxiliary electrode electrically connected with the second electrodeincreases the equivalent thickness of the second electrode.

(2) in the electroluminescent diode array substrate provided by at leastone embodiment of the present disclosure, the resistance of the secondelectrode is reduced, and the problem that the large voltage drop causedby the large resistance of the second electrode in a case where thesecond electrode made of metallic silver with a thinner thickness isavoided.

(3) in the electroluminescent diode array substrate provided by at leastone embodiment of the present disclosure, the problem of damaging anorganic light-emitting display panel due to the large voltage drop isavoided.

The following points need to be explained:

(1) The drawings of the embodiments of the present disclosure are onlyrelated to the structures related to the embodiments of the presentdisclosure, and other structures can refer to general designs.

(2) For clarity, in the drawings for describing the embodiments of thepresent disclosure, a thickness of a layer or a thickness of a region isexaggerated or reduced, that is, these drawings are not drawn accordingto an actual scale. It should be understood that: in a case where anelement such as a layer, a film, a region or a substrate is referred toas being disposed “on” or “beneath” another element, the element may be“directly” disposed “on” or “beneath” another element, or anintermediate element may be provided.

(3) In the absence of conflict, the embodiments of the presentdisclosure and the features in the embodiments can be combined with eachother to obtain new embodiments.

What is described above is related to the illustrative embodiments ofthe disclosure only and not limitative to the scope of the disclosure.Therefore, the scopes of the disclosure are defined by the accompanyingclaims.

1. An electroluminescent diode array substrate, comprising: a basesubstrate, and an auxiliary electrode, a pixel definition layer, a firstelectrode, a functional layer, and a second electrode which are disposedon the base substrate, wherein the pixel definition layer is providedwith a via hole structure; the auxiliary electrode is disposed on atleast one side of the via hole structure; and the second electrode iselectrically connected with the auxiliary electrode.
 2. Theelectroluminescent diode array substrate according to claim 1, whereinan upper surface of the auxiliary electrode is higher than an uppersurface of the functional layer in the via hole structure.
 3. Theelectroluminescent diode array substrate according to claim 1, whereinthe auxiliary electrode is a structure in a U shape.
 4. Theelectroluminescent diode, array substrate according to claim 1, whereinthe auxiliary electrode is a plate-type structure; or there are aplurality of auxiliary electrodes which are spaced apart from eachother.
 5. The electroluminescent diode array substrate according toclaim 3, wherein a conductive polymer layer is provided in the via holestructure, and the second electrode is electrically connected with theauxiliary electrode by the conductive polymer layer.
 6. Theelectroluminescent diode array substrate according to claim 5, wherein athickness of the conductive polymer layer is less than a thickness ofthe pixel definition layer.
 7. The electroluminescent diode arraysubstrate according to claim 5, wherein a conductivity of the conductivepolymer layer is greater than 10⁻⁶ S/m.
 8. The electroluminescent diodearray substrate according to claim 5, wherein a material of theconductive polymer layer comprises at least one of polypyrrole,polyphenylene sulfide, polyphthalocyanine, polyaniline andpolythiophene.
 9. The electroluminescent diode array substrate accordingto claim 5, further comprising a planarization layer disposed betweenthe base substrate and the pixel definition layer, wherein the via holestructure extends from the pixel definition layer and penetrates throughthe planarization layer.
 10. The electroluminescent diode arraysubstrate according to claim 9, wherein a thickness of the conductivepolymer layer is larger than a thickness of the planarization layer, andthe thickness of the conductive polymer layer is smaller than a sum ofthe thickness of the planarization layer and a thickness of the pixeldefinition layer.
 11. The electroluminescent diode array substrateaccording to claim 9, wherein an upper surface of the conductive polymerlayer is flush with an upper surface of the pixel definition layer. 12.The electroluminescent diode array substrate according to claim 9,wherein there are a plurality of via hole structures penetrating throughthe planarization layer and the pixel definition layer, and the secondelectrode is electrically connected with the auxiliary electrode by theplurality of via hole structures.
 13. The electroluminescent diode arraysubstrate according to claim 9, wherein a thickness of the functionallayer is from about 100 nm to about 300 nm, a thickness of the auxiliaryelectrode is from about 0.5 μm to about 1 μm, a thickness of theplanarization layer is from about 1 μm to about 3 μm, a thickness of thepixel definition layer is from about 1 μm to about 3 μm, and a thicknessof the conductive polymer layer is from about 2 μm to about 5.7 μm. 14.The electroluminescent diode array substrate according to claim 13,wherein the functional layer comprises at least one of a light-emittinglayer, an electron injection layer, an electron transmission layer, ahole injection layer and a hole transmission layer.
 15. A display panel,comprising the electroluminescent diode array substrate according toclaim
 1. 16. A method of manufacturing an electroluminescent diode arraysubstrate, comprising: providing a base substrate, forming an auxiliaryelectrode, a pixel definition layer, a first electrode, a functionallayer and a second electrode on the base substrate, wherein the pixeldefinition layer is provided with a via hole structure; the auxiliaryelectrode is disposed on at least one side of the via hole structure;and the second electrode is electrically connected with the auxiliaryelectrode.
 17. The manufacturing method according to claim 16, whereinan upper surface of the auxiliary electrode which is formed on at leastone side of the via hole structure is higher than an upper surface ofthe functional layer in the via hole structure.
 18. The manufacturingmethod according to claim 16, before forming the auxiliary electrode,further comprising: forming a planarization layer on the base substrate,wherein the via hole structure extends from the pixel definition layerand penetrates through the planarization layer.
 19. The manufacturingmethod according to claim 16, further comprising: forming a conductivepolymer layer in the via hole structure, wherein the second electrode iselectrically connected with the auxiliary electrode by the conductivepolymer layer.
 20. The manufacturing method according to claim 19,wherein the conductive polymer layer is formed by an inkjet printingmethod.